1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
|
/*
* Copyright (c) 2009, 2010, 2013, 2022
* Phillip Lougher <phillip@squashfs.org.uk>
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2,
* or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*
* lzma_wrapper.c
*
* Support for LZMA1 compression using LZMA SDK (4.65 used in
* development, other versions may work) http://www.7-zip.org/sdk.html
*/
#include <LzmaLib.h>
#include "squashfs_fs.h"
#include "compressor.h"
#define LZMA_HEADER_SIZE (LZMA_PROPS_SIZE + 8)
static int lzma_compress(void *strm, void *dest, void *src, int size, int block_size,
int *error)
{
unsigned char *d = dest;
size_t props_size = LZMA_PROPS_SIZE,
outlen = block_size - LZMA_HEADER_SIZE;
int res;
res = LzmaCompress(dest + LZMA_HEADER_SIZE, &outlen, src, size, dest,
&props_size, 5, block_size, 3, 0, 2, 32, 1);
if(res == SZ_ERROR_OUTPUT_EOF) {
/*
* Output buffer overflow. Return out of buffer space error
*/
return 0;
}
if(res != SZ_OK) {
/*
* All other errors return failure, with the compressor
* specific error code in *error
*/
*error = res;
return -1;
}
/*
* Fill in the 8 byte little endian uncompressed size field in the
* LZMA header. 8 bytes is excessively large for squashfs but
* this is the standard LZMA header and which is expected by the kernel
* code
*/
d[LZMA_PROPS_SIZE] = size & 255;
d[LZMA_PROPS_SIZE + 1] = (size >> 8) & 255;
d[LZMA_PROPS_SIZE + 2] = (size >> 16) & 255;
d[LZMA_PROPS_SIZE + 3] = (size >> 24) & 255;
d[LZMA_PROPS_SIZE + 4] = 0;
d[LZMA_PROPS_SIZE + 5] = 0;
d[LZMA_PROPS_SIZE + 6] = 0;
d[LZMA_PROPS_SIZE + 7] = 0;
/*
* Success, return the compressed size. Outlen returned by the LZMA
* compressor does not include the LZMA header space
*/
return outlen + LZMA_HEADER_SIZE;
}
static int lzma_uncompress(void *dest, void *src, int size, int outsize,
int *error)
{
unsigned char *s = src;
size_t outlen, inlen = size - LZMA_HEADER_SIZE;
int res;
outlen = s[LZMA_PROPS_SIZE] |
(s[LZMA_PROPS_SIZE + 1] << 8) |
(s[LZMA_PROPS_SIZE + 2] << 16) |
(s[LZMA_PROPS_SIZE + 3] << 24);
if(outlen > outsize) {
*error = 0;
return -1;
}
res = LzmaUncompress(dest, &outlen, src + LZMA_HEADER_SIZE, &inlen, src,
LZMA_PROPS_SIZE);
if(res == SZ_OK)
return outlen;
else {
*error = res;
return -1;
}
}
static void lzma_usage(FILE *stream)
{
fprintf(stream, "\t (no options) (deprecated - no kernel support)\n");
}
struct compressor lzma_comp_ops = {
.init = NULL,
.compress = lzma_compress,
.uncompress = lzma_uncompress,
.options = NULL,
.usage = lzma_usage,
.id = LZMA_COMPRESSION,
.name = "lzma",
.supported = 1
};
|
